mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-29 05:51:10 +00:00
94ca2c0894
The test tst-strtod-underflow covers various edge cases close to the underflow threshold for strtod (especially cases where underflow on architectures with after-rounding tininess detection depends on the rounding mode). Make it use the type-generic machinery, with corresponding test inputs for each supported floating-point format, so that other functions in the strtod family are tested for underflow edge cases as well. Tested for x86_64.
463 lines
14 KiB
C
463 lines
14 KiB
C
/* Test for strtod handling of arguments that may cause floating-point
|
|
underflow.
|
|
Copyright (C) 2012-2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
/* Defining _LIBC_TEST ensures long double math functions are
|
|
declared in the headers. */
|
|
#define _LIBC_TEST 1
|
|
#define __STDC_WANT_IEC_60559_TYPES_EXT__
|
|
#include <errno.h>
|
|
#include <fenv.h>
|
|
#include <float.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <tininess.h>
|
|
|
|
#include "tst-strtod.h"
|
|
|
|
/* Logic for selecting between tests for different formats is as in
|
|
tst-strtod-skeleton.c, but here it is selecting string inputs with
|
|
different underflow properties, rather than generated test
|
|
data. */
|
|
|
|
#define _CONCAT(a, b) a ## b
|
|
#define CONCAT(a, b) _CONCAT (a, b)
|
|
|
|
#define MEMBER(FSUF, FTYPE, FTOSTR, LSUF, CSUF) \
|
|
const char *s_ ## FSUF;
|
|
|
|
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
|
|
# define CHOOSE_ld(f,d,...) d
|
|
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 && LDBL_MIN_EXP == -16381
|
|
# define CHOOSE_ld(f,d,ld64i,...) ld64i
|
|
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 && LDBL_MIN_EXP == -16382
|
|
# define CHOOSE_ld(f,d,ld64i,ld64m,...) ld64m
|
|
#elif LDBL_MANT_DIG == 106 && LDBL_MAX_EXP == 1024
|
|
# define CHOOSE_ld(f,d,ld64i,ld64m,ld106,...) ld106
|
|
#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
|
|
# define CHOOSE_ld(f,d,ld64i,ld64m,ld106,ld113,...) ld113
|
|
#else
|
|
# error "unknown long double format"
|
|
#endif
|
|
|
|
#define CHOOSE_f(f,...) f
|
|
#define CHOOSE_f32(f,...) f
|
|
#define CHOOSE_d(f,d,...) d
|
|
#define CHOOSE_f64(f,d,...) d
|
|
#define CHOOSE_f32x(f,d,...) d
|
|
#define CHOOSE_f128(f,d,ld64i,ld64m,ld106,ld113,...) ld113
|
|
|
|
#if __HAVE_FLOAT64X
|
|
# if FLT64X_MANT_DIG == 113 && FLT64X_MAX_EXP == 16384
|
|
# define CHOOSE_f64x(f,d,ld64i,ld64m,ld106,ld113,...) ld113
|
|
# elif (FLT64X_MANT_DIG == 64 \
|
|
&& FLT64X_MAX_EXP == 16384 \
|
|
&& FLT64X_MIN_EXP == -16381)
|
|
# define CHOOSE_f64x(f,d,ld64i,...) ld64i
|
|
# else
|
|
# error "unknown _Float64x format"
|
|
# endif
|
|
#endif
|
|
|
|
#define _XNTRY(FSUF, FTYPE, FTOSTR, LSUF, CSUF, ...) \
|
|
CHOOSE_ ## FSUF (__VA_ARGS__),
|
|
#define XNTRY(...) \
|
|
GEN_TEST_STRTOD_FOREACH (_XNTRY, __VA_ARGS__)
|
|
|
|
#define TEST(f, d, ld64i, ld64m, ld106, ld113, u) \
|
|
{ XNTRY(f, d, ld64i, ld64m, ld106, ld113) u }
|
|
|
|
enum underflow_case
|
|
{
|
|
/* Result is exact or outside the subnormal range. */
|
|
UNDERFLOW_NONE,
|
|
/* Result has magnitude at most half way between the largest
|
|
subnormal value and the smallest positive normal value, and is
|
|
not exact, so underflows in all rounding modes and independent
|
|
of how tininess is detected. */
|
|
UNDERFLOW_ALWAYS,
|
|
/* Result is positive, with magnitude larger than half way between
|
|
the largest subnormal value and the least positive normal
|
|
value, but would underflow when rounded to nearest to normal
|
|
precision, so underflows after rounding in all modes except
|
|
rounding upward. */
|
|
UNDERFLOW_EXCEPT_UPWARD,
|
|
/* Likewise, for a negative result, underflowing after rounding
|
|
except when rounding downward. */
|
|
UNDERFLOW_EXCEPT_DOWNWARD,
|
|
/* Result is positive, with magnitude at least three quarters of
|
|
the way from the largest subnormal value to the smallest
|
|
positive normal value, so underflows after rounding only when
|
|
rounding downward or toward zero. */
|
|
UNDERFLOW_ONLY_DOWNWARD_ZERO,
|
|
/* Likewise, for a negative result, underflowing after rounding
|
|
only when rounding upward or toward zero. */
|
|
UNDERFLOW_ONLY_UPWARD_ZERO,
|
|
};
|
|
|
|
struct test
|
|
{
|
|
GEN_TEST_STRTOD_FOREACH (MEMBER)
|
|
enum underflow_case c;
|
|
};
|
|
|
|
static const struct test tests[] =
|
|
{
|
|
TEST ("0x1p-126",
|
|
"0x1p-1022",
|
|
"0x1p-16382",
|
|
"0x1p-16383",
|
|
"0x1p-969",
|
|
"0x1p-16382",
|
|
UNDERFLOW_NONE),
|
|
TEST ("-0x1p-126",
|
|
"-0x1p-1022",
|
|
"-0x1p-16382",
|
|
"-0x1p-16383",
|
|
"-0x1p-969",
|
|
"-0x1p-16382",
|
|
UNDERFLOW_NONE),
|
|
TEST ("0x0p-10000000000000000000000000",
|
|
"0x0p-10000000000000000000000000",
|
|
"0x0p-10000000000000000000000000",
|
|
"0x0p-10000000000000000000000000",
|
|
"0x0p-10000000000000000000000000",
|
|
"0x0p-10000000000000000000000000",
|
|
UNDERFLOW_NONE),
|
|
TEST ("-0x0p-10000000000000000000000000",
|
|
"-0x0p-10000000000000000000000000",
|
|
"-0x0p-10000000000000000000000000",
|
|
"-0x0p-10000000000000000000000000",
|
|
"-0x0p-10000000000000000000000000",
|
|
"-0x0p-10000000000000000000000000",
|
|
UNDERFLOW_NONE),
|
|
TEST ("0x1p-10000000000000000000000000",
|
|
"0x1p-10000000000000000000000000",
|
|
"0x1p-10000000000000000000000000",
|
|
"0x1p-10000000000000000000000000",
|
|
"0x1p-10000000000000000000000000",
|
|
"0x1p-10000000000000000000000000",
|
|
UNDERFLOW_ALWAYS),
|
|
TEST ("-0x1p-10000000000000000000000000",
|
|
"-0x1p-10000000000000000000000000",
|
|
"-0x1p-10000000000000000000000000",
|
|
"-0x1p-10000000000000000000000000",
|
|
"-0x1p-10000000000000000000000000",
|
|
"-0x1p-10000000000000000000000000",
|
|
UNDERFLOW_ALWAYS),
|
|
TEST ("0x1.000000000000000000001p-126",
|
|
"0x1.000000000000000000001p-1022",
|
|
"0x1.000000000000000000001p-16382",
|
|
"0x1.000000000000000000001p-16383",
|
|
"0x1.000000000000000000001p-969",
|
|
"0x1.00000000000000000000000000000000000000001p-16382",
|
|
UNDERFLOW_NONE),
|
|
TEST ("-0x1.000000000000000000001p-126",
|
|
"-0x1.000000000000000000001p-1022",
|
|
"-0x1.000000000000000000001p-16382",
|
|
"-0x1.000000000000000000001p-16383",
|
|
"-0x1.000000000000000000001p-969",
|
|
"-0x1.00000000000000000000000000000000000000001p-16382",
|
|
UNDERFLOW_NONE),
|
|
TEST ("0x1p-150",
|
|
"0x1p-1075",
|
|
"0x1p-16446",
|
|
"0x1p-16447",
|
|
"0x1p-1075",
|
|
"0x1p-16495",
|
|
UNDERFLOW_ALWAYS),
|
|
TEST ("-0x1p-150",
|
|
"-0x1p-1075",
|
|
"-0x1p-16446",
|
|
"-0x1p-16447",
|
|
"-0x1p-1075",
|
|
"-0x1p-16495",
|
|
UNDERFLOW_ALWAYS),
|
|
TEST ("0x1p-127",
|
|
"0x1p-1023",
|
|
"0x1p-16383",
|
|
"0x1p-16384",
|
|
"0x1p-970",
|
|
"0x1p-16383",
|
|
UNDERFLOW_NONE),
|
|
TEST ("-0x1p-127",
|
|
"-0x1p-1023",
|
|
"-0x1p-16383",
|
|
"-0x1p-16384",
|
|
"-0x1p-970",
|
|
"-0x1p-16383",
|
|
UNDERFLOW_NONE),
|
|
TEST ("0x1p-149",
|
|
"0x1p-1074",
|
|
"0x1p-16445",
|
|
"0x1p-16446",
|
|
"0x1p-1074",
|
|
"0x1p-16494",
|
|
UNDERFLOW_NONE),
|
|
TEST ("-0x1p-149",
|
|
"-0x1p-1074",
|
|
"-0x1p-16445",
|
|
"-0x1p-16446",
|
|
"-0x1p-1074",
|
|
"-0x1p-16494",
|
|
UNDERFLOW_NONE),
|
|
TEST ("0x1.fffffcp-127",
|
|
"0x1.ffffffffffffep-1023",
|
|
"0x1.fffffffffffffffcp-16383",
|
|
"0x1.fffffffffffffffcp-16384",
|
|
"0x1.ffffffffffffffffffffffffffp-970",
|
|
"0x1.fffffffffffffffffffffffffffep-16383",
|
|
UNDERFLOW_NONE),
|
|
TEST ("-0x1.fffffcp-127",
|
|
"-0x1.ffffffffffffep-1023",
|
|
"-0x1.fffffffffffffffcp-16383",
|
|
"-0x1.fffffffffffffffcp-16384",
|
|
"-0x1.ffffffffffffffffffffffffffp-970",
|
|
"-0x1.fffffffffffffffffffffffffffep-16383",
|
|
UNDERFLOW_NONE),
|
|
TEST ("0x1.fffffep-127",
|
|
"0x1.fffffffffffffp-1023",
|
|
"0x1.fffffffffffffffep-16383",
|
|
"0x1.fffffffffffffffep-16384",
|
|
"0x1.ffffffffffffffffffffffffff8p-970",
|
|
"0x1.ffffffffffffffffffffffffffffp-16383",
|
|
UNDERFLOW_ALWAYS),
|
|
TEST ("-0x1.fffffep-127",
|
|
"-0x1.fffffffffffffp-1023",
|
|
"-0x1.fffffffffffffffep-16383",
|
|
"-0x1.fffffffffffffffep-16384",
|
|
"-0x1.ffffffffffffffffffffffffff8p-970",
|
|
"-0x1.ffffffffffffffffffffffffffffp-16383",
|
|
UNDERFLOW_ALWAYS),
|
|
TEST ("0x1.fffffe0001p-127",
|
|
"0x1.fffffffffffff0001p-1023",
|
|
"0x1.fffffffffffffffe0001p-16383",
|
|
"0x1.fffffffffffffffe0001p-16384",
|
|
"0x1.ffffffffffffffffffffffffff80001p-970",
|
|
"0x1.ffffffffffffffffffffffffffff0001p-16383",
|
|
UNDERFLOW_EXCEPT_UPWARD),
|
|
TEST ("-0x1.fffffe0001p-127",
|
|
"-0x1.fffffffffffff0001p-1023",
|
|
"-0x1.fffffffffffffffe0001p-16383",
|
|
"-0x1.fffffffffffffffe0001p-16384",
|
|
"-0x1.ffffffffffffffffffffffffff80001p-970",
|
|
"-0x1.ffffffffffffffffffffffffffff0001p-16383",
|
|
UNDERFLOW_EXCEPT_DOWNWARD),
|
|
TEST ("0x1.fffffeffffp-127",
|
|
"0x1.fffffffffffff7fffp-1023",
|
|
"0x1.fffffffffffffffeffffp-16383",
|
|
"0x1.fffffffffffffffeffffp-16384",
|
|
"0x1.ffffffffffffffffffffffffffbffffp-970",
|
|
"0x1.ffffffffffffffffffffffffffff7fffp-16383",
|
|
UNDERFLOW_EXCEPT_UPWARD),
|
|
TEST ("-0x1.fffffeffffp-127",
|
|
"-0x1.fffffffffffff7fffp-1023",
|
|
"-0x1.fffffffffffffffeffffp-16383",
|
|
"-0x1.fffffffffffffffeffffp-16384",
|
|
"-0x1.ffffffffffffffffffffffffffbffffp-970",
|
|
"-0x1.ffffffffffffffffffffffffffff7fffp-16383",
|
|
UNDERFLOW_EXCEPT_DOWNWARD),
|
|
TEST ("0x1.ffffffp-127",
|
|
"0x1.fffffffffffff8p-1023",
|
|
"0x1.ffffffffffffffffp-16383",
|
|
"0x1.ffffffffffffffffp-16384",
|
|
"0x1.ffffffffffffffffffffffffffcp-970",
|
|
"0x1.ffffffffffffffffffffffffffff8p-16383",
|
|
UNDERFLOW_ONLY_DOWNWARD_ZERO),
|
|
TEST ("-0x1.ffffffp-127",
|
|
"-0x1.fffffffffffff8p-1023",
|
|
"-0x1.ffffffffffffffffp-16383",
|
|
"-0x1.ffffffffffffffffp-16384",
|
|
"-0x1.ffffffffffffffffffffffffffcp-970",
|
|
"-0x1.ffffffffffffffffffffffffffff8p-16383",
|
|
UNDERFLOW_ONLY_UPWARD_ZERO),
|
|
TEST ("0x1.ffffffffffp-127",
|
|
"0x1.fffffffffffffffffp-1023",
|
|
"0x1.ffffffffffffffffffffp-16383",
|
|
"0x1.ffffffffffffffffffffp-16384",
|
|
"0x1.ffffffffffffffffffffffffffffffp-970",
|
|
"0x1.ffffffffffffffffffffffffffffffffp-16383",
|
|
UNDERFLOW_ONLY_DOWNWARD_ZERO),
|
|
TEST ("-0x1.ffffffffffp-127",
|
|
"-0x1.fffffffffffffffffp-1023",
|
|
"-0x1.ffffffffffffffffffffp-16383",
|
|
"-0x1.ffffffffffffffffffffp-16384",
|
|
"-0x1.ffffffffffffffffffffffffffffffp-970",
|
|
"-0x1.ffffffffffffffffffffffffffffffffp-16383",
|
|
UNDERFLOW_ONLY_UPWARD_ZERO),
|
|
};
|
|
|
|
/* Return whether to expect underflow from a particular testcase, in a
|
|
given rounding mode. */
|
|
|
|
static bool
|
|
expect_underflow (enum underflow_case c, int rm)
|
|
{
|
|
if (c == UNDERFLOW_NONE)
|
|
return false;
|
|
if (c == UNDERFLOW_ALWAYS)
|
|
return true;
|
|
if (TININESS_AFTER_ROUNDING)
|
|
{
|
|
switch (rm)
|
|
{
|
|
#ifdef FE_DOWNWARD
|
|
case FE_DOWNWARD:
|
|
return (c == UNDERFLOW_EXCEPT_UPWARD
|
|
|| c == UNDERFLOW_ONLY_DOWNWARD_ZERO);
|
|
#endif
|
|
|
|
#ifdef FE_TOWARDZERO
|
|
case FE_TOWARDZERO:
|
|
return true;
|
|
#endif
|
|
|
|
#ifdef FE_UPWARD
|
|
case FE_UPWARD:
|
|
return (c == UNDERFLOW_EXCEPT_DOWNWARD
|
|
|| c == UNDERFLOW_ONLY_UPWARD_ZERO);
|
|
#endif
|
|
|
|
default:
|
|
return (c == UNDERFLOW_EXCEPT_UPWARD
|
|
|| c == UNDERFLOW_EXCEPT_DOWNWARD);
|
|
}
|
|
}
|
|
else
|
|
return true;
|
|
}
|
|
|
|
static bool support_underflow_exception = false;
|
|
volatile double d = DBL_MIN;
|
|
volatile double dd;
|
|
|
|
static bool
|
|
test_got_fe_underflow (void)
|
|
{
|
|
#ifdef FE_UNDERFLOW
|
|
return fetestexcept (FE_UNDERFLOW) != 0;
|
|
#else
|
|
return false;
|
|
#endif
|
|
}
|
|
|
|
#define TEST_STRTOD(FSUF, FTYPE, FTOSTR, LSUF, CSUF) \
|
|
static int \
|
|
test_strto ## FSUF (int i, int rm, const char *mode_name) \
|
|
{ \
|
|
const char *s = tests[i].s_ ## FSUF; \
|
|
enum underflow_case c = tests[i].c; \
|
|
int result = 0; \
|
|
feclearexcept (FE_ALL_EXCEPT); \
|
|
errno = 0; \
|
|
FTYPE d = strto ## FSUF (s, NULL); \
|
|
int got_errno = errno; \
|
|
bool got_fe_underflow = test_got_fe_underflow (); \
|
|
char buf[FSTRLENMAX]; \
|
|
FTOSTR (buf, sizeof (buf), "%a", d); \
|
|
printf ("strto" #FSUF \
|
|
" (%s) (%s) returned %s, errno = %d, " \
|
|
"%sunderflow exception\n", \
|
|
s, mode_name, buf, got_errno, \
|
|
got_fe_underflow ? "" : "no "); \
|
|
bool this_expect_underflow = expect_underflow (c, rm); \
|
|
if (got_errno != 0 && got_errno != ERANGE) \
|
|
{ \
|
|
puts ("FAIL: errno neither 0 nor ERANGE"); \
|
|
result = 1; \
|
|
} \
|
|
else if (this_expect_underflow != (errno == ERANGE)) \
|
|
{ \
|
|
puts ("FAIL: underflow from errno differs from expectations"); \
|
|
result = 1; \
|
|
} \
|
|
if (support_underflow_exception \
|
|
&& got_fe_underflow != this_expect_underflow) \
|
|
{ \
|
|
puts ("FAIL: underflow from exceptions " \
|
|
"differs from expectations"); \
|
|
result = 1; \
|
|
} \
|
|
return result; \
|
|
}
|
|
|
|
GEN_TEST_STRTOD_FOREACH (TEST_STRTOD)
|
|
|
|
static int
|
|
test_in_one_mode (size_t i, int rm, const char *mode_name)
|
|
{
|
|
return STRTOD_TEST_FOREACH (test_strto, i, rm, mode_name);
|
|
}
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
int save_round_mode __attribute__ ((unused)) = fegetround ();
|
|
int result = 0;
|
|
#ifdef FE_TONEAREST
|
|
const int fe_tonearest = FE_TONEAREST;
|
|
#else
|
|
const int fe_tonearest = 0;
|
|
# if defined FE_DOWNWARD || defined FE_TOWARDZERO || defined FE_UPWARD
|
|
# error "FE_TONEAREST not defined, but another rounding mode is"
|
|
# endif
|
|
#endif
|
|
#ifdef FE_UNDERFLOW
|
|
feclearexcept (FE_ALL_EXCEPT);
|
|
dd = d * d;
|
|
if (fetestexcept (FE_UNDERFLOW))
|
|
support_underflow_exception = true;
|
|
else
|
|
puts ("underflow exception not supported at runtime, only testing errno");
|
|
#endif
|
|
for (size_t i = 0; i < sizeof (tests) / sizeof (tests[0]); i++)
|
|
{
|
|
result |= test_in_one_mode (i, fe_tonearest,
|
|
"default rounding mode");
|
|
#ifdef FE_DOWNWARD
|
|
if (!fesetround (FE_DOWNWARD))
|
|
{
|
|
result |= test_in_one_mode (i, FE_DOWNWARD,
|
|
"FE_DOWNWARD");
|
|
fesetround (save_round_mode);
|
|
}
|
|
#endif
|
|
#ifdef FE_TOWARDZERO
|
|
if (!fesetround (FE_TOWARDZERO))
|
|
{
|
|
result |= test_in_one_mode (i, FE_TOWARDZERO,
|
|
"FE_TOWARDZERO");
|
|
fesetround (save_round_mode);
|
|
}
|
|
#endif
|
|
#ifdef FE_UPWARD
|
|
if (!fesetround (FE_UPWARD))
|
|
{
|
|
result |= test_in_one_mode (i, FE_UPWARD,
|
|
"FE_UPWARD");
|
|
fesetround (save_round_mode);
|
|
}
|
|
#endif
|
|
}
|
|
return result;
|
|
}
|
|
|
|
#define TEST_FUNCTION do_test ()
|
|
#include "../test-skeleton.c"
|